Guest post by Willem Theus, PhD Researcher (KULeuven, cotutelle with UCLouvain)
The history of private international law (or ‘conflict of laws’) is incomplete. Private international law textbooks have always referred to the essentials of the history of our discipline. However, these essentials are often solely based on the history of conflict of laws in the West and on the works of western authors such as Huber, Von Savigny and Story. It is undoubtedly true that these authors played an important role and that the “modern” conflict of laws finds it origin in 19thcentury Europe, when the split between private and public international law occurred. This is however only one part of history.
Conflict of laws systems have been around much longer and are definitely not uniquely western. They were already present in the very first civilizations, with some rules of that ancient history still resembling our present-day rules.Conflict of laws is “the body of law that aims to resolve claims involving foreign elements”. A state or international border is therefore not required to have a conflict of laws system, only different jurisdictions and laws (i.e. legal pluralism) are. A distinction could therefore be made between “external” (i.e. crossing an international State border) conflict of laws or private international law and “internal” conflict of laws (i.e. within one State). Both the historical research and the contemporary study of our field should arguably reflect much more on precolonial and/or non-western conflict of laws systems and on the unique linkage between the national (or “internal”) and international (or “external”) spheres. This is especially so given that “external” conflict of laws rules seem to sometimes guide “internal” conflict of laws cases. I offer one historical example to highlight the new perspectives that such a widening of scope could offer.
In a not so distant and colonial past, there were multiple “internationalized” or mixed courts in various regions and nations. The last such mixed court only closed its doors in 1980. In general, mixed courts were local courts that employed a mixed (read mostly Western) bench, bar and legal system to deal with legal conflicts that had a mixed or “foreign” element, i.e. conflicts not exclusively related to one local or foreign resident population. Those exclusively local or intra-foreigner -of the same nationality- legal conflicts were often dealt with by various local or consular courts. The mixed or “foreign” element was however often widely interpreted and therefore quickly kicked in, leading to overlapping jurisdictions in many instances and therefore to a conflict of laws system.
An example of such a set-up is the Tangier International Zone (1923-1956), a treaty-based multinational run zone, which remained under the Sovereignty of the Sultan of Morocco. It had various multinational institutions with local involvement. In the Zone, five different legal systems co-existed, each with their own courts. These were the American Consular Court, the Special Tribunal of the State Bank of Morocco, the Moroccan Sharia courts, the Moroccan Rabbinical courts and the Mixed Court. The latter dealt with all cases that had a “foreign” element (except American as they went to the aforementioned American Consular Court). Both “internal” and “external” conflict of law systems in fact overlap here. Indeed the Mixed Court and the two Moroccan courts were “local” courts with the judges being formally appointed by the Sultan, whereas the American Consular Court was in essence an ad hoc American court in Tangier. The Special Tribunal was some sort of early investment protection court with very limited jurisdiction.
Naturally, in such a set-up conflict of laws cases were frequent, as illustrated by the Toledano-case which came before the Mixed Court. In 1949 a dispute between the heirs of the large inheritance of a Tangerine Jew, Isaac Toledano, broke out. The key question concerned the nationality of Isaac – and as such the questions of jurisdiction and applicable law. During his lifetime Isaac had become a Spanish citizen by naturalization, yet he had seemingly always lived in Morocco. Had he somehow lost his Moroccan citizenship? If so, the mixed courts would have jurisdiction and Spanish law would apply, leading his inheritance to be divided under all his children, including his married daughters. If not, the rabbinical courts of Tangier and rabbinical law would apply, leading to his inheritance to only go to his sons and unmarried daughters. On appeal the court overturned the judgment of first instance that held that he had retained his Moroccan nationality. He was deemed to be Spanish and therefore Spanish law was to be applied.
Such jurisdictional caselaw is only a part of this conflict of laws treasure trove. The caselaw of the mixed courts seemingly encompasses all types of conflict of laws questions and many other legal questions. I have to say seemingly, as the caselaw of the mixed courts has in recent times barely been studied and their archives (if known at all) are scattered throughout the globe. A closer look could undoubtedly open up new perspectives to conflict of laws, and some of these mixed courts’ experiences and case-law could perhaps help to guide ever-recurring questions of personal status matters regarding foreigners. The Emirate of Abu Dhabi has for example reintroduced special personal status provisions for non-Muslim foreigners as reported on conflictoflaws recently. The courts also offer new perspectives for public international law as certain mixed courts acted as “true” international courts when interpreting their treaties. An example is the Court of Appeal of Mixed Court of Tangier going against the International Court of Justice in 1954 when it held that it alone had the authority to provide authoritative interpretations of the Zone’s constitutive treaties. The Mixed Courts could even open new perspectives to EU-law as many early key EU lawyers and judges have ties to certain Mixed Courts. Much work is therefore still to be done. This piece is a call to arms for just that.
 Hatzimihail, N.E. (2021) Preclassical Conflict of Laws. Cambridge University Press 51-52.
 For an overview of this period see: Banu, R. (2018). Nineteenth Century Perspectives on Private International Law. Oxford University Press
 Yntema, Hessel E. (1953). The Historic Bases of Private International Law. The American Journal of Comparative Law, vol. 2, no. 3, 301. Yntema refers to the following text found in a Fayoum Papyri: “Contracts between Greeks-who had established colonies in Egypt (red.)-and Egyptians, if in Greek form, should be tried before the chrematists, the Greek courts; if in Egyptian form, before the laocrites, the native courts, in accordance with the laws of the country.”
 Okoli, C.S.A. (2020). Private International Law in Nigeria. Hart, 3.
 Okoli, Op.cit., 3-7; Yntema. Op.cit., 299
 For a good overview of the different meanings of this term see: Benda-Beckmann, B. & Turner, B. (2018). Legal Pluralism, Social Theory, and the State. Journal of Legal Pluralism and Unofficial Law, 50(3), 255–274
 This distinction is not new and is used in legislation. See for example: Non-application of This Regulation to Internal Conflicts of Laws. (2016). In A. Calvo Caravaca, A. Davì, & H. Mansel (Eds.), The EU Succession Regulation: A Commentary (pp. 521-529). Cambridge University Press.
 Okoli Op.cit, 3.
 Pacific Manuscripts Bureau, Collection MS 1145: Judgements of the Joint Court of the New Hebrides. Retrieved from <https://asiapacific.anu.edu.au/pambu/catalogue/index.php/judgements-of-joint-court-of-new-hebrides> accessed 13 December 2021. It was known as a ‘Joint’ Court and not ‘Mixed’ as there were only two powers involved: France and the UK. Although in French it was still referred to as a Tribunal Mixte. Mixed Courts mostly existed in countries that were not-directly colonized, yet still under heavy Western influence such as Siam, China and Egypt. They were mostly founded due to western distrust for the local legal systems and build forth on the principle of personal jurisdiction (and the connected later principle of extraterritoriality and the connected Capitulations and Unequal Treaties).
 Erpelding, M. (2020). Mixed Courts of the Colonial Era. In Hélène Ruiz Fabri (ed), Max Planck Encyclopedia of International Procedural Law. Oxford University Press.
 Erpelding, M & Rherrousse, F. (2019) The Mixed Court of Tangier. In Héne Ruiz Fabri (ed), Max Planck Encyclopedia of International Procedural Law. Oxford University Press, paras 22-24.
 de Radigues de Chenneviere, C. (5 April 1949). ‘Procès Toledano’. Tangier, P 452/717, AF-12-A-3 (Diplomatic Archives of the Kingdom of Belgium)
 Grawitz, M. (1955). Arrêt du 13 août 1954. Annuaire français de droit international, 1(1), 324–328
 Erpelding, M. (2020). International law and the European Court of Justice: the Politics of Avoiding History, Journal of the History of International Law, 22(2-3), 446-471.